Now, as the couple marks their 65th anniversary, the gruff, no-nonsense personality of Prince Philip, 91, is being celebrated in a book of his many quips and verbal faux pas. Prince Philip: Wise Words and Golden Gaffes has been compiled by Phil Dampier and former royal correspondent Ashley Walton.

When it comes to the secret to his marriage, Prince Philip has had plenty to say. Here are five of his most memorable quotes from the book on matters of the heart – and the rest of the body: